Draw rolling mill



July 28; 1959 J. B. TIEDEMANN DRAW ROLLING MILL Original Filed Oct. 26,1955 a Sheets-Shet 1' INI fENTOR.

Julzus B.T1edemann BY M M AT TOR N EYS.

July 28, 1959 .12. TIEDEMANN 2,395,435

DRAW ROLLING MILL Original Filedoct. 26, 1953 8 Sheets-Sheet 2 22:: M MaQ ll Q i .4 ."A

g INKENTOR.

Julzus B.T1edemann BY w M I Q AT ToRMEYs.

July 28, 1 J. B. TIEDEMANN DRAW ROLLING MILL 8 She'ets-Shee'h 3 OriginalFiled Oct. 26, 1953 INVENTOR.

3 Julius B.Tiedemann AT TO RN EYS.

y 1959 J. B. TIEDEMANN 2, I

bRAw ROLLING MILL Original Filed (Jet. 26, 1953 8 sheets sheet =11 4 'l{/60} amss in {/69 4 ZP ss 8 I \4/58] lPAss INVENTORH Julius B.TiedemannBY Z PRESSURE T BRAKE- ATTORNEYS.

July 28, 1959 J. a. TIEDEMANN DRAW ROLLING MILL 8 Sheets-Sheet 6 r g nalFiled om. '2e, 1955 y 1959 J. B. TIEDEMANN 2,896,485

. DRAW ROLLING MILL Original Filed Oct. 26. 1953 a Sheets-Sheet 7 l6 M4Jullus B.Tiedemann I M- VIM ATTORNEYS.

ATTORNEYS.

July 28, 195 J. B. TIEDEMANN DRAW ROLLING MILL s Sheets-Sheet 8 OriginalFiled Oct. 26. 1955 JuZiusBIiedemann BY find m4 M United States Patent()fiice 2,896,485 DRAW ROLLING MILL Julius B. Tiedemann, Milwaukee,Wis., assignor to A. O. Smith Corporation, Milwaukee, Wis., acorporation of ,New York Continuation of abandoned application SerialNo. 388,177, October 26, 1953. This application March 26, 1954,

Serial N0. 418,966

13 Claims. or. 80-19) a single blank heating and eliminates thenecessity for expensive reheating of the blanks for subsequent passes.

The present rolling mill is provided with certain novel safety featureswhich prevent freezing of the machine and automatically relieve orrelease the pressure roll when excessive pressures are encountered,thereby preventing damage of the mechanism and eliminating downtime forunfreezing the machine and placing it back in operation.

More specifically, the rolling mill is provided with a pressure rollwhich is lowered and raised by a toggle mechanism. The closing andopening ofthe toggle mechanism is accomplished by oscillation of acam-actuated rocker arm acting through a rod connecting the togglemechanism and the rocker arm. Adjacent the end of the rod connected tothe rocker arm, a safety device is provided for automatically openingthe toggle mechanism which thereby releases the pressure roll shouldtheroll pressure exceed a predetermined maximum amount.-

By aseries of adjustments the rolling mill may be predeterminately setfor making one, two, or three automatic passes at a heated blank placedtherein and when successive passes are employed the pressure roll maybepredeterminately set to take progressively larger bites at the blank. Toattain progressively varying bites by the pressure roll on succeedingautomatic passes, an eccentrio mounted on an upper toggle pivot shaft iscausedto rotate a predetermined amount aftereach pass thereby loweringthe center of the pivot a predetermined amount. The lowered upper togglepivot reflects a corresponding lowering of the roll when the togglemechanism is again closed for the next succeeding pass. Rotation of theupper toggle shaft a predetermined amount is brought about by a seriesof stop-controlled racks and gears actuated by a pair of air cylinderscontrolled by cam-actuated solenoid valves.

The rolling mill may be set for single pass operation or for two orthree successive automatic passes by a series of cam systems which areoperated from a driven shaft' The cams operate switchesflfor controllinga clutch in accordance with the number ofpasses to be made, and in thecase of successive automatic passes they also operate switches forsolenoid valves which control the flow of air to air cylinders forsetting the pressure roll height for each succeeding automatic pass.

The drawings furnished herewith illustrate the best mode of,carrying outthe invention as presentlycontemplated'and set forth hereinafter. I

Inthe drawings:

Figure 1 is a side elevation this. invention;

Fig. 2 is a top plan view of the. ,rolling mill;

of the draw rolling mill of Patented July 28, 1959 Fig. 3 is a frontelevation of the rolling mill;

Fig. 4 is an enlarged fragmentary view partially in section showing thepressure roll trunnioned in its bear" Fig. 5 is an enlarged fragmentaryside view of Fig. 4 partially in section showing the pressure rollsuspensron; a

Figs. 6 and 7 are enlarged fragmentary sectional views showing thesealing means between the pressure roll and the bearings;

Fig. 8 is a side elevation of part of the rolling mill; of thisinvention taken on the side opposite that of Figure 1 showing the rollsetting mechanism;

Fig. 9 is a fragmentary extension of Fig. 8 and shows the means forautomatically setting the rolling mill for a predetermined number ofpasses;

Fig. l0 is an enlarged fragmentary view partially in' section showingthe stop sleeve adjustment mechanism;

Fig. 11 is a sectional end view of the stop sleeve adf justmentmechanism; i

Fig. 12 is an enlarged sectional view taken on line 12 -1 2 of Fig. 8;

Fig. 13 is a diagrammatic view showing the safety mechanism forrelieving the pressure roll;

Fig. 14 is a diagrammatic View showing the safety mechanism in thetripped position with. the connecting rod between the toggle mechanismand the rocker arm dropped to an ineffective position;

Fig. 15 is a diagrammatic view showing the electrical system controllingthe brake and clutch valve; Fig. 16 is an enlarged front view showingthe means for setting the rolling mill for a predetermined number ofautomatic passes; Fig. 17 is a top plan view of the means roll shown inFig. 16;

Fig. 18 is an end view of the means for setting the roll shown in Fig.16; a e a Fig. 19 is a diagrammatic view similar to Fig. 16 showing infull lines certain elements efiective during the single pass operation;

Fig. 20 is a diagrammatic view similar to Fig. 19

for setting the with a pass control rod set for two pass operation showthe second pass of a two pass operation;

ing in full lines certain elements etfective during the first pass; fl

Fig. 21 is a diagrammatic view similar to Fig. 20 showing in full linescertain elements effective durin Fig. 22 is a diagrammatic view similarto Fig. 19 with the pass control rod set for three pass operationshowing in full lines certain elements effective during the first pass;

Fig. 23 is a diagrammatic view similar to Fig. 22' showing in full linescertain elements effective durin the second pass of a three passoperation; and

Fig. 24 is a diagrammatic view similar to Fig. 22 showing in full linescertain elements eifect ive during the third pass of a three passoperation. e

As shown in the drawings, the rolling mill comprises a'base structure 1which rests in a pit provided in a foundation 2 and supports a pneumaticair cushion 3.

The pneumatic air cushion 3 is comprised generally of a stationaryplunger 4 secured to the base 1 and a cylin-: der 5 disposed forvertical movement relative to the plunger. A compressible fiuid, such asair is introduced within cylinder 5 through a suitable line, not shown,and serves to cushion the downward thrusts of the roll.

A generally rectangular lower crosshead 6 is mounted. centrally oncylinder 5. A plurality of tie rods 7 extend vertically upward throughcrosshead 6 adjacent the corners thereof and continue upwardly throughvertical frame elements -8. The upper extremities of tie rods, 7-

5 are adapted to receive a generally rectangular upper;

crosshead 9 which is secured against relative movement with respect tothe rods by suitable bolts which are threaded on the upper ends of therespective rods. The underside of crosshead 9 is provided with atransverse cavity 10in which working roll 11 is mounted. The weight ofthe crossheads 6 and 9, their connecting tie rods 7, and the workingroll 11 are counterbalanced by the pneumatic air cushion 3. Thesemembers move as a unit against the compressible fluid in the air cushion3 as they are caused to be lowered during operation.

The trunnions 12 of roll 11 are mounted in split bearipgs 13 secured tothe underside of crosshead 9. To more efiectively withstand the heat towhich the roll and its bearings may be subjected, the trunnions 12 andbearings '13 may be. provided with coolant channels, not shown, throughwhich water or other coolant can be circulated. The bearings 13 areprovided with a finished horizontal upper surface 14 which bears againsta complementary lower surface 15 of crosshead 9. A plurality of threadedmembers 16 extend downwardly through the crosshead 9 and are threadedlyengaged within suitable openings in the bearings 13. To retain surfaces14 and 15 in contact and prevent relative vertical movement of thebearings and roll with respect to the crosshead, nuts 17 threadedlyengage'the members 16. Suitable lock plates are provided to secure thenuts 17 from turning.

To set the original working height of, the roll 11, shims, not shown, ofpredetermined thickness may be inserted between the surfaces 14 and 15of the bearings and crosshead, respectively.

The bearings 13 are secured against transverse movement with respect tothe crosshead 9 by a pair of keeper plates 18 which are formed on theouter ends of bearings 13. The plates 18 are provided with a verticallyextendingslot 19 adjacent their ends through which threaded members 20secure the projections to the crosshead 9, thereby preventing transversemovement of the bearing relative to the crosshead. The slots 19 permitlimited vertical movement of the bearing and roll for the purpose ofinserting the aforementioned shims between the complementary bearing andcrosshead surfaces 14 and 15, respectively.

Although bearings 13 are precluded from relative movement with respecttothe crosshead 9, the roll 11, supported in the bearings, is permittedlimited axial movement with respect to the. bearings by sealing meansdisposed therebetween.

The sealing means includes a stepped wearplate ring ll which is securedto the roll 11 radially outward of the trunnions 12. A thrust washer 22is disposed between the wearplate 21 and the bearing 13. A pair ofcomplementary sealing rings 23 and 24 are disposed radially outward ofwasher 22 and between and in bearing relationship with hearing 13 andwear plate 21. The ring 24 is generally spaced from the ring 23 and isprovided with a flange which overlaps the ring 23 radially outwardly. Agroove 25 is provided in the periphery of ring 23 and has an -ring 26composed of a material having high heat withstanding properties, such assilicone rubber, disposed therein between the complementary rings. 23and, 24 to seal the passage therebetween from scale or other foreignmatter which the roll may pick up from the blank being rolled. While theroll 11 ro-. tates within bearing 13, the sealing rings 23 and 24 arefree to rotate relatively to the roll and, the hearing, but areprecluded from relative rotation with respect to each other by aplurality of circum'ferentially spaced dowel pins 27 disposed withinaligned holes 28 in the rings. The length of dowel pins 27 is such as topermit limited axial movement of roll 11 relative, to bearings 13.

The opposed ends of each alternate pair of aligned holes 28 are recessedto provide a spring cavity 29 adapted to. receive a helical spring 30which encompasses the respective pin 27, as shown in Fig. 6. Springs 30normally retain the rings 23. and 24' in contact with the '4 bearing 13and wear plate 21, respectively, and thereby prevent foreign matter fromentering the hearing. The described sealing means further permitslimited relative axial movement of the roll with respect to the bearing,takes up any slack due to wear between the members, and allows forexpansion of the roll due to the heat inherent in the draw rollingoperation.

The bed 31 of the rolling mill rests on foundation 2 and is disposedbetween the upper crosshead 9- and lower crosshead 6; The bed 31 extendstransversely between the frame elements 8, the latter being secured tothe bed in any suitable, manner. On the, upper surface of the bed,longitudinal ways 32 are provided on whichv a. platen 33 is disposed forsliding recip-rocatory' motion. A die member 34 for forming a heatedblank 35 is removably secured on platen 33. Longitudinal tracks or spankplates 36 are preferably removably secured on the platen 33 along thelongitudinal edges of the die member 34 on which the working roll isadapted to bear on its final pass at the: blank. It, is desirable thatthe upper-surfaces: of the spankplates be coextensive. with the uppersurface of the blank upon completion of the final rolling pass. As onealternative method of setting the initial height of roll 11, withrespect to the die member, shims, not shown, of predetermined. thicknessmay be inserted between the platen. 33 and the spank plates. 36.

To reciprocate platen 33 on :ways 32 one. end of a 37 is pivotallyattached, to the rearward portion of the platen. The other end of link37 is pivotally secured between the upper end of a, bifurcated. beam 38.The lower end of beam 38, is, pivotally mounted on shaft 39 supported inbearings mounted on the frame. Pivotalmovement of beam 38 on shaft: 39.imparts a reciprocatory movement to platen 33, through the link 37.

To additionally support the frame and drive mech-. anism of the rollingmill, aplurality of columns. 4.0. ext-- tend upwardly from thefoundation 2 to the frame.

Movement is imparted to beam 38 and the limits of reciprocation ofplaten 33 are. established by a, connect. ing rod 41 which is pivotallymounted at. one end on a shaft, 42 extending transversely through beamelement- 38. When a shorter reciprocating, stroke of the platen 33 isdesired, the shaft 42 with mounted connecting rod 41 may be. moved toposition 43, of the bifurcated beam 38, thereby decreasing the pivotallimits of beam 38 about: shaft 39.

The driven end of connecting rod 41 is disposed about an eccentric 44which is keyed on rotatable shaft 45 mounted in the frame, of themachine. As the shaft 45 is caused to rotate, the eccentric 44 causesconnecting, rod; 41 to oscillate beam 38 resulting in reciprocating,straight; line motion of the platen 33.

Rotation of roll 11 during the working stroke of platen, 33 may beeffected by the pressure between the. roll and the blank 35 or betweenthe roll, the blank and the spank? plates 36, or the roll may bepositively driven. The. latter may be accomplished by positivelyimparting rotaa tion to the working roll 11 by movement of the platen33. A rack 46, with its teeth disposed downwardly is secured to theunderside of platen 33 and engages gear 47 which is mounted on shaft 48supported by the bed. of the machine and a bed extension 49. A clutch 50is provided on shaft 48 so that the rotary motion of gear 47 is impartedto shaft 48 only during the working stroke of the platen. A second gear51 is keyed on shaft 48. and acts through a train of gears 52, 53 and 54whose speed reduction imparts the platen speed to the working rollperiphery, the latter gear 54 being keyed to the, working roll trunnion12.

The gear train driving the roll- 11 is arranged to compensate for rollheight adjustments to be described here inafter and remains enmeshedduring lower and raising of'the roll. A link 55 is pivotally mounted onshaft 48 and provides a bearing member for gears 52 and 53. Thepivotallymounted link 55 permits gears 52 and 53 to belts or the like.

rotate about gear 51 but retains gears 52 and 53 in a fixed positionwith respect to each other. A link 56 connects the bearing for gear 53with that of gear 54 and thereby limits or restricts the pivotalmovement of link 55 about shaft 48. Thus, as roll 11 is lowered for theworking stroke, link 55 pivots counterclockwise and moves gears 52 and53 to the left as viewed in Figure 1, yet retains the drive gearsenmeshed. As the roll is raised the link 55 pivots clockwise and retainsthe gear entrainment. i

To raise and lower the working roll 11 in proper sequence with theplaten stroke, a toggle mechanism 57 is employed. The upper toggle linkconsists of a bell crank 58 which is mounted at its upper end to pivoton an eccentric 59. The eccentric 59 in turnis keyed to the upper toggleshaft 60 and is adapted to rotate therewith. The shaft 60 is rotatablymounted in bearings 61 which are provided in the bed of the machine. J

The lower toggle link 62 is pivotally attached to bell crank 58 at thecenter pivot 63 of the toggle mechanism. The lower toggle link ispivotally mounted on a shaft 64 which is fixedly secured to the upperside of the lower crosshead 6 in vertical alignment with upper toggleshaft 60. To lower the roll 11 the toggle mechanism 57 is moved into itsclosed position; i.e., the center pivot 63 is moved rearwardly or verynearly into vertical align ment with thetoggle shaft 60 and 64, causingthe connected crossheads 6 and 9 and 'working roll 11 to move downwardlywithin the lower crosshead guide brackets 65 affixed to the bed 31against the pressure .fluid in the air cushion 3. The roll 11 is raisedby the action of the toggle mechanism 57 when the same is opened; i.e.,the

center pivot 63 is moved forwardly.

The toggle mechanism 57, as shown in Figure 1, is sequentially closedand opened by a connecting rod 66 which is at one end pivotallyconnected to bell crank 58, as indicated at 67. The rod 66 is actuatedby a rocker arm 68 which is connected to the other end of rod 66 througha safety mechanism to be hereinafter described. The rocker arm 68 isdisposed to pivot about a shaft 69 mounted on the frame of the mill andis pivotally actu ated by a pair of cams 70 and 71 fixedly secured onshaft 45. A pair of follower rollers 72 and 73 disposed on rocker arm68, are alternately in engagement with the respective actuating portionsof cams 70 and 71. As

the earns 70 and 71 rotate with shaft 45 and cause rocker arm 68 topivot about its shaft 69, the toggle mechanism 57 is correspondinglyclosed and opened, the cam sequence and timing corresponding to theworking stroke of platen 33.

To rotate eccentric shaft 45 and thus operate platen 33 and raise andlower the roll 11 through toggle mechanism 57 in timed sequence with theplaten, a large drive gear 74 is fixedly secured on shaft 45. Drive gear74 is motivated by the train oj gears 75, 76 and 77 adapted to producethe desired speed reduction. A motor 78 may be utilized to drive therolling mill with the motor torque being transferred from the motorsheave 79 to a clutch sheave 80 having an attached flywheel by a seriesof An air clutch 81 is provided within resulting in damaged parts, orthe outright fracture of parts. In either case down-time resultsandexpensive repairs are necessary. v p

The rolling mill of the present invention is equipped with safetyfeatures to prevent overloading of the working roll with consequentdamage. Figures 1, l3, and 14 show a safety mechanism associated withthe connecting rod 66 which will release the toggle mechanism 57 whenthe roll 11 encounters an overload.

The safety mechanism, as best shown in Figures 1, 13 and 14, includes apair of brackets 84 attached to rod 66 which pivotally support an air;cylinder 85. A piston 86 is.disposed rearwardly'within the cylinder 85,see Fig. 13, and is normally retained in that position by the. cylinderpressure. The piston rod extends rearwardly'from cylinder 85 and ispivotally attached to one end of a bell crank 87 at pivot 88. The rockerarm end of the ,connecting rod 66 is bifurcated and is pivotallyattached to the center pivot 89 of bell crank 87. Theopposite end ofbell crank 87 is pivotally attached to rocker arm 68 at pivot 90.Beneath the normally operativeposition of pivot 90, as shown in Figs.1.and l3, bell crank 87 is provided with an enlarged portion 91 which isdisposed between the bifurcation of the rod 66. and abuts against anadjusting screw 92 which is disposed on the "rod '66 and one of whichprojects upwardly through the bifurcation. v The pressure in cylinder 85normally acts against piston 86 to maintain the bell crank surface 91against the adjusting screw 92. With the bell crank so disposed thepivot 90 between bell crank 87 and rocker arm 68 remains offset adistance Y from the center line of rod 66. During normal operation, thesafety mechanism merely oscillates with the rod 66. [I

The maximum load at which the rolling mill will normally operate is theproduct of the. cylinder pressure acting through a moment arm X, whichis the distance between the piston rod center line and pivot 89 ,of thebell crank 87. If in the course ofoperation. the toggle mechanism 57will not close due to excessive pressures encountered by roll 11, therocker arm 68 being positively actuated by cam 70 will impose a forceacting through the offset distance Y whichwill .overcome the cylinderpressure acting through distance X. The force will unseat the bell cranksurface 91 from its normal position on adjusting screw 92 causing thebell crank to pivot at 89 thereby forcing piston 86 forwardly againstthe cylinder pressure. The action of the safety mechanism is best shownin Figs. 13 and 14. In Fig. 14, the rod 66 is shown in the droppedposition. With the safety mechanism so disposed the connecting rod 66will be free of clutch sheave 80 on shaft 82 which is mounted on theframe of the machine. The gear 77 is fixedly secured on the clutch shaft82 and accordingly, when the clutch is engaged, gear 77 through its geartrain rotates shaft 45 and places the platen 33 and roll 11 inlongitudinal and vertical motion, respectively. An air-operated bandtype brake 83 on shaft 82 may be activated to stop the mechanism. Withthe drive arrangement described the motor may remain in operationindependently of the rolling mechanism.

Machines of the type described are generally built to the action of therocker arm and the roll 11 will be re lieved by the air pressure inbalancing cylinder 3.

If the roll encounters an excessive load during actual rollingwhen thetoggle mechanism 57 is fully closed, the force acting to break or openthe toggle is transmitted through rod 66 and acts through offsetdistance Y to overcome the cylinder pressure as before and drop the rod66, thereby releasing the toggle mechanism 57 and relieving the roll.After the undue stress has been safely relieved the cylinder pressurewill reset the safety mechanism. i

The safety mechanism described may be set for varying maximum loads byadjusting the pressure in cylinder or by adjusting the distance Y bymeans of the screw 92 tions in the length of connecting rod 66 will varythe distance between the dead center'position of the toggle and the.toggle center pivot for the fully closed mechanism. According to thewell-known formulas gov:

the toggle will close almost to a straight line.

er-ning toggle operation, it is known that for a given maximum forcetransmitted through rod '66, the toggle load varyinversely as thedistancebetween the toggle dead center position and the toggle centerpivot for the fully closed mechanism. Therefore, as this distance isincreased the toggle will support -a decreased load for a givenforcetransmitted through rod 66. Conversely, where this distance isdecreased, the toggle will support an increased load for the same forcetransmitted through :IQd 66. Thus, as the length of the connecting rod66 is increased by means of the turnbuckle nut 93, the safety mechanismwill be caused t'o-open for a lesser maximum .toggle load. Conversely,as the length of the connecting rod is decreased, the safety mechanismwill open for a mill permits more effective and efficient utilization ofthe heating to which the blank is previously subjected. With aconventional single pass rolling mill, the apparatus must be reset foreach pass and the heat loss of the blank is generally so great as torequire reheating before each pass. The present invention provides forsetting the rolling mill in advance for up to three passes so that thepasses are quickly and automatically made before the blank becomes toocold to draw roll.

When only a single pass on the heated blank is to be .made, the properoperating roll height with respect to the die member may be attained byshimming down the roll or shimming up the die member 34 or spank plates36 to the height desired. To attain uniformity among a plurality ofsingle pass rolled blanks the roll should be adjusted so that it willroll on the spank plates 36 and stress the tie rods a given amount foreach blank being drawn rolled. Strain gauges, not shown, may assist inthe shim adjustment.

When multiple passes are to be made on the heated blank, the roll heightfor the first pass is adjusted as described above except that on thefirst pass the working .roll will roll only on the blank and will nottouch the "spank plates 36. For additional automatic passes the .rollheight is adjusted by eccentric 59 which is rotated within the uppertoggle link 58. As eccentric 59 is rotated a given amount the-uppertoggle shaft 60 is lowered, and on any subsequent pass, the roll isfurther correspondingly lowered. In order to attain uniformity among aplurality of blanks for multiple pass operation, the eccentric 59should, for the final pass, set the work- .ing roll to roll on spankplates 36 and stress the tie rods a predetermined amount.

To rotate eccentric 59 and thereby adjust the roll height, a gear 94 iskeyed to the upper toggle shaft 60. Rotation of gear 94 effects acorresponding rotation of the eccentric. Gear 94 is rotated by a rack 95which is slidably disposed in bracket 96 affixed to the bed of themachine. The end of rack 95 is fixedly secured to a shaft 97 of afloating gear 98. The floating gear 98 is disposed for engagement with apair of diametrically opposed racks 99 and 100.

' The upper rack 99 is slidably disposed in guide bracket 101 secured tothe bed of the machine, and a rod 102 disposed rearwardly therefromextends slidably through a stop sleeve 103. I

fThe Iowerrack 100 is slidably disposed in guide bracket 104 secured tothe bed of themachine, and a ass-6,488

rod 105 disposed rearwardly therefrom extends slidably through stopsleeve. 106. j

Racks 99 and 100, respectively, have projections S107 and 108,.disposedrearwardly thereof, for engagement with stop sleeves 103 .and 106. Asthe rack '99 is moved rearwardly through stop sleeve 103 the gear 93 isrotated moving the rack 95 rearwardly a given amount. Rack '95 in turn.actuates gear 94 a given amount which sets the eccentric 59 for the nextsucceeding pass. A like operation of rack results in a further rotationof eccentric 59. In three passoperation the roll height is sequentially.set for the second and third passes by racks 99 and 100. In two passoperation the roll height is set for the second pass by rack 99.

.To actuate the racks 99 and 100 and thereby set the working roll heightfor. succeeding passes, the ends of the racks are provided with pistons.109 and 110, respectively, which are disposed in air cylinders 1'11 and112, respectively. Air entering the cylinder 111 in front of the piston109 drives the piston rearwardly to actuate the rack 99until theprojection 107 on the rack abuts against the stop sleeve 103. The lowerrack 100 is operated in like manner. The cylinders 111 and 112 are alsoprovided with air inlets rearwardly of the pistons in order to reset theroll for each subsequent blank to be rolled. Two-way'solenoid valves 113and 114, respectively, control the entry of air into cylinders 111 and112 from a source, not shown.

Aswas previously pointed out, the angle through which eccentric 59 isrotated by the racks 99 and 100, to thereby lower the working roll isestablished by the distance between the respective rack projections 107and 108 and their corresponding stop sleeves 103 and 106. Theserespective distances may be varied by modifying the stop sleevepositions. A pair of housings 115 and 116 are disposed, respectively,about the sleeves 103 and 106 and are fixedly secured to the frame ofthe machine. Sleeves 103 and'106 are adapted to move longitudinallythrough the housings and are externally threaded. Within upper housing115 an internally threaded nut 117 is threadedly engaged with the sleeve103 with the nut being fixedly secured to the housing. Thus, as thesleeve is rotated it moves rearwardly or forwardly with respect to thenut 117.

A bevel gear 118 is disposed loosely on the sleeve adjacent nut 117. Alongitudinal spline groove 119 is provided in the sleeve 103 and a key120 disposed in groove 119 locks the bevel gear 118 and sleeve 103 fromrelative rotational movement with respect to each other but permitsrelative longitudinal movement between these members. As the bevel gear118 is rotated the threaded sleeve 103 is turned through the stationarynut 117, thereby moving the sleeve longitudinally relative to the gearwith key 120 sliding in spline groove 119,

A second bevel gear 121 engages gear 118 and is actuated by a shaft 122which extends outside of the housing. A handwheel 123 may be employed toturn the shaft and thereby set the stop sleeve 103 at a predeterminedposition which in turn establishes the predetermined roll height for thesecond pass.

The stop sleeve adjustment for the lower rack 100 is similar to thatdescribed for the upper rack 99. A stationary nut 124' engages theexternally threaded sleeve 106. A bevel gear 125 is disposed about thesleeve with a key 126 engaging a spline groove 127 to lock the gear andsleeve from relative rotational movement yet permitting relativelongitudinal movement between the members. A bevel gear 128, having ashort shaft 129 extending downwardly outside the housing 116, 'actuatesbevel gear 125. .A gear 130 is affixed to shaft 129 below housing 116and engages a gear 131. The shaft 132 of .gear 131 extends upwardlyadjacent shaft 122 and is likewise provided with a handwheel 133. Theoperation of the lover sleeve adjustment is similar to that described inconnection with the upper sleeve adjustment with both sleeves beingemployed to, predeterminately set. the. roll height for three passoperation.

To set the stop sleeves 183 and 106 the roll height desired, a gauge isprovided to show the roll height or the extent of the changes in height.An idler 134 and i gear 135 transmit the motion of gear, 94 actuated bythe with graduated marks is secured to the frame of the machine adjacentthe rack 136. As the I rack 136 is caused to move relative to the gaugeplate 137, the change .in roll height is readily discernible to theoperator. The

stop sleeve adjustment can thereby be accurately set. The mechanism forsetting the rolling mill for a predetermined number of automatic passesis shown in detail in Figures 15 through 24. A sprocket 138, see Fig, 9,is secured on the eccentric shaft 45 and drives sprocket 139 secured onshaft 140 by means of roller chain 141. The shaft 140 extends throughand is' supported by a housing member 142 secured to the frame of themachine. A gear 143 is secured on shaft 140 on the opposite side of thehousing 142 from sprocket 139 and is driven by the sprocket, and in turndrives an idler gear 144 and a series of gears 145, 146, and 147. Thepitch diameter of the respective gears are such that gear 145 is adaptedto move with half the speed of gear 143 and gears 146 and 147 areadapted to move with one-third of the speed of gear 143. The shaft 148for idler-144 and the shafts 149, 150 and 151 for the respective gears145, 146, and 147 are all horizontally aligned with sprocket shaft 140and are transversely parallel to each other.

The shafts 148, 150 and 151 extend through. housing member 142 and aresupported thereby. The shaft 148 for idler 144 is supported by housing142 butdoes not extend therethrough.

On the opposite side of housing 142- from the enmeshed gears 143, 145,146 and 147, respectively, a series of cams are mounted on the shafts140, 149, 150 and 151. A switch operating cam 152 is mounted on shaft140. Shaft 149 has mounted thereon two cams, a switch operating cam 153and adjacent thereto a dog activating cam 154. A dog activating cam 155,longitudinally aligned with cam 154, is mounted on shaft 150. Shaft 151is also provided with two cams, a switch operating cam 156 and a dogactivating cam 157, the latter being in longitudinal alignment with dogactivating cams 154 and 155. The arrangement of the foregoing mechanismis such that as eccentric shaft 45 is rotated, the shafts 140,- 149, 150and 151 and their aifixed cams are rotated simultaneously, with the cams153 and 154 on shaft 149 rotating at half the speed of cam 152 on shaft140, and cam 155 on shaft 150 and cams 156 and 157 on shaft 151rotatingat one-third the speed of cam 152 on shaft 140. While cam 152 makes onecomplete revolution for each pass of the roll, the cams 153 and 154 makeone complete revolution for two passes of the roll, and earns 155, 156and 157 make one complete revolution for three passes of the roll.

To actuate the main clutch 81 and brake 83 in accordance with the numberof roll passes desired, switches 158, 159 and 160 are placed inoperating arrangement with cams 152, 153, and 156, respectively.Switches and in serieswith a solenoid openated air valve 164 whichcontrols the air from a source, not'shown, to the clutch 81 and brake83. The timing of the respective'cams determines the length of time theswitches remain-closed and accordingly elfectuates the drive for one,two or 10 three passes, respectively, of the roll. As will be describedhereinafter only one of the switches 158, 159, and 160 is effective at agiven time while the other two remain inetfective.

Figs. 15 and 16 show switches 158, 159, and 160 as being retained openbefore "a pass or a sequence of passes is begun by engagement of theraised portion of the cams 152, 153 and 156 with the respective switchdogs. Until the raised portion of the cams 152, 153 and 156 roll olftheir respective dogs, the switches remain open and the roll drivecannot be actuated. In order to start the drive from this position,hand-operated switches 165, 166 and 167 are placed in parallel,respectively, withswitches .158, 159, and 160. When manually closed, thehand switch corresponding to the number of passes to be made actuatesthe solenoid valve 164 to release the brake and engage the clutch 81 andthereby places the drive in and thereby closes the cam operated switchfor that circuit,

As was pointed out earlier, when the clutch 81 is engaged, the switchoperating cams 152, 153, and 156 all rotate simultaneously at theirvarying speeds to actuate their respective switch dogs. As was furtherpointed out only one of the switches 158, 159, or 160 are actuallyeffective at any given time depending on the number of passes of theroll desired. To effectuate but one of the switches 158, 159, or 160, asecond switch is placed in series with the respective switches as bestillustrated in the electrical diagram of Fig. 15. For single passoperation the switch 168 is closed as will be described hereinafter, andthereby switch 158 is efiectuated. For two pass operation the switch 169is closed eifectuating switch 159, and for three pass operation theswitch .170 is closed elfectuating switch 160.

To close the switches 168, 169, and 170, switch dogs 171, 172, and 173are provided thereon, respectively. As shown in Fig. 16 the switches168, 169, and 170 are longitudinally spaced and longitudinally alignedwith respect to each other.

To set the rolling mill for a predetermined number of passes, a controlrod 174 is disposed in suitable guides for longitudinal movement abovethe switch dogs 171, 172, and 173 for switches 168, 169, and 170,respectively, and above dog activating cams 154, 155, and 157. Adownwardly projecting cam 175 is aflixed forwardly on rod 174, and isdisposed to actuate the switch dogs 171, 172, and 173 as the rod ismoved longitudinally. The switch dogs are spaced so that earn 175 mayengage but one dog at a time and thereby close the corresponding switch.In Figs. 16 and 19, cam 175 is shown closing switch 168 thereby settingthe rolling mill for single pass operation. In Fig. 20 and 21 the cam175 is shown closing switch 169 thereby setting the roll for two passoperation. And in Figs. 22 through 24 the switch has been closed by camthereby setting the roll for three pass operation.

Mechanism is provided for the operator to set the .control rod 174 atthe forward end of the machine. A rack .176 extends forwardly from therod 174 and is engaged by a small spur gear 177. The shaft 178 of gear177 extends vertically downward and is rotatably supported by the frameof the machine. A pinion gear 179 is rafiixed to the lower end of theshaft 178 as shown in Fig. 9. A rack 180 extends rrearwardly of aconnecting rod 181 and engages the pinion 179 such that longitudinalmovement of the rod 181 effects a like movement of control rod 174. Theconnecting rod 181 extends forwardly to the front end of the rollingmill through suitable guide brackets and is pivotally secured to anactuating lever 182. The lower end of lever 182 is pivotally mounted onthe shaft for gear 135. A notched roll setting bracket 183 is fixedlysecured on the of the machine above 1 the position vof connecting rodsecurement on lever 182 and is disposed longitudinally adjacentthelever. The bracket 183 is provided with three spaced notches 184,185, and 186 on its upper surface to be engaged by a pawl 187 connectedto the lever. The notches of bracket 183 are spaced and positioned sothat when pawl 187 engages notch 184, the cam 175 on control rod 174will actuate switch dog 171 and thereby close switch 168 setting themachine for single pass operation. Moving the lever 182 to engage pawl187 in notch 185 will move cam 175 to actuate switch dog 172 and therebyset the machine for two pass operation. When pawl .187 is placed intoengagement with notch 186,'the cam 175 will actuate switch dog 1'73 andset the rolling mill for three pass operation.

After either or both of the stop sleeves 103 and 106 have beenpredeterminately set by utilizing their respective handwheels 123 and133 to set the roll height in accordance with the pattern of operation,solenoid valves 113 and 114 operate to automatically set the roll heightin proper sequence by controlling the air supply to cylinders 111 and112, respectively. To automatically control the operation of either orboth of the solenoid valves 113 and 114, three dogs 188, 189, and 190are pivotally mounted on the control rod 174. The dogs 188, 189, and 190are disposed on rod 174 in the same vertical plane as the dog activatingcams 154, 155, and 157 mounted respectively on shafts 149, 150, and 151.The dogs are spaced on the control rod 174 so that when the rolling millis set for two pass operation the dog 188 will be engaged and lifted bycam 154 While the other dogs remain ineffective. When the control rod isset for three pass operation dog 189 will be engaged and lifted by cam155 and dog 190 will be engaged and lifted by cam 157 while dog 188remains ineifective. When the rolling mill is set for single passoperation all of the dogs remain ineffective. Figs. 16 through 24 showin detail the various control rod positions and the operation of dogs188, 189, and 190.

Longitudinally aligned above the control rod 174 are three valveswitches 191, 192, and 193 with depending switch dogs 194, 195, and'196, respectively. The switches 191 and 192 are connected in paralleland actuate solenoid valve 113 while switch 193 actuates solenoid valve114. The switches 191, 192, and 193 are spaced from each other so thatwhen dog 188 is engaged and lifted by cam 154, the dog will engageswitch dog 194 and thereby close switch 191 actuating solenoid valve113. With cam 154 making one revolution for two passes of the roll itshould be noted that the solenoid valve activating portion of the cam isdisposed on the second pass portion of the cam, the first pass beingmade at initial roll height without eccentric adjustment.

When control rod 174 is in position for three pass operation, dog 189will engage switch dog 195, and dog 190 will engage switch dog 196 ofswitches 192 and 193, respectively. Cams 155 and 157 make one completerevolution for three passes of the rolling mill. On the first passinitial roll height without eccentric adjustment is utilized and thus onthe first one-third revolution of the cams neither cam actuates itscorresponding valve switch. On the second pass, cam 155 actuatessolenoid valve 113 and sets the roll height accordingly, while cam 157remains inactive. On the third pass cam 155 continues to hold closedswitch 192 to actuate valve 113 while cam 157 has now also closed switch193 to actuate solenoid valve 114, thereby resetting the roll for thefinal pass at the blank.

To operate the rolling mill of the present invention the operator mustpredeterminately set the machine for the desired number of passes to bemade on the blank and for the desired roll height at which succeedingpasses are to be made.

In the case of three pass operation, the roll height for plate or thedie members or any combination thereof. The second pass roll height isadjusted by setting the upper stop sleeve 103 by means of handwheel 123so that when the air is applied to cylinder 111 ahead of piston 109 theeccentric 59 on the upper toggle shaft 60 will be turned the properamount. Stop sleeve 106 is similarly set by handwheel 133 to positioneccentric '59 properly for the third pass. Further, the lever 182 mustbe placed in notch 186 of the notched bracket 183. With the lever 182 sodisposed, cam 175 on control rod 174 will close switch and set therolling mill for three pass operation as shown in Figs. 22 through 24.With the roll adjustments and the lever 182 set for three passes, theheated blank is then placed on the die member and locked in place bysuitable gripper mechanism, not shown.

To place the machine in motion for three passes the hand operated switch167 is closed activating solenoid valve 164 to disengage the brake 83and engage clutch 81. The clutch will then remain engaged for onerevolution of cam 156 or for a time period equivalent to three passes ofthe rolling mill. At the proper time in the pass sequence, cams 155 and157 will close switches 192 and 193, respectively, activating thesolenoid valves 113 and 114, respectively, to thereby lower the rollheight for the working strokes of the last two passes. When the cam 156has completed a revolution, the raised portion of the cam will strikeswitch dog 163 opening switch 160, thereby deactivating solenoid valve164 and disengaging the clutch and applying the brake. The switches 1'92and 193 will also be opened as the cams 155 and 157 allow dogs 189 and190, respectively, on control rod 174 to fall to their inactiveposition, thereby deactivating the solenoid valves 113 and 114 andpermitting the introduction of air into the cylinders 111 and 112 behindthe pistons 109 and 110 to return the working roll to its initialheight. The blank is then removed, completing the three pass operation.

When more than one pass is to be made upon the blank it is generallydesirable to preheat the roll and the die members prior to operation sothat heat transfer from the blank to those members will be minimized.The preheatis readily accomplished bymeans of a gas flame. A pipe 197provided with a plurality of spaced gas orifices and connected by aflexible tube to a gas source is placed in suitable hook membersadjacent the roll. A similar pipe 198 is spaced above the die member.With gas pipes 197 and 198 so disposed the machine is run through asingle, interrupted pass to complete the preheat.

For two pass operation the roll height for the initial pass may be setin the manner hereinbefore described in connection with the first passof a three pass operation. For the second pass the upper stop sleeve 103is set by handwheel 123 as in the case for the second pass of three passoperation. The lever 182 is then set in notch 185 of notched bracket 183setting control rod 174 for two pass operation. With the control rod'sodisposed cam will close switch 169. The hand operated switch 166 is thenclosed energizing the solenoid 164 to engage the clutch and start therolling mill in motion. The clutch will remain engaged for onerevolution of cam 153 for a time period equivalent to two passes of therolling mill. In proper sequence cam 154 will close switch 191activating solenoid 113 to set the roll height for the second pass, asshown in Fig. 21. On completion of the two pass operation the clutch isagain disengaged by engagement of the raised portion of switch cam 153with dog 162 to set the brake and the roll is returned to its initialheight by reversing the air incylinder 111 as solenoid valve 113 isdeenergized and eccentric 59 returned to its initial position.

When desired, cams and switches may be arranged so that both cylinders111 and 112 are placed in operation to activate racks 99 and 100 on thesecond pass of two pass operation to set the roll height.

1 In the case of single pass operation, the roll height is simplyadjusted byshims as described in connection with the first pass of twoor three pass operation. Lever 182 is set for one pass operation withcam 175 of control rod174 closing switch 168. Hand switch 165 is thenclosed to set the rolling mill in motion, and after a single pass thecam 152 will open switch 158 and thereby disengage the clutch and setthe brake to stop the operation of the machine. Where desired, cams andswitches may also be provided to set the roll for single pass operationby utilizing one or both cylinders 111 and 112'to activateoneor bothracks 99 and 100.

This application constitutes a continuation of my copending applicationSerial No. 388,l77 filed October 26, 1953, for DrawRolling Mill, nowabandoned.

Various modes of carrying out the invention are contemplated as withinthe scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

I claim: I

I 1. In a metal forming apparatus wherein a blank is formed between apair of pressure members with one of the members being disposed forvertical movement relative to the other of the members, a frame, arotatable member disposed on said frame, a toggle mechanisminterconnecting the rotatable member and a movable pressure member toefliect vertical movement of said movable member in accordance withopening and closing of the toggle mechanism, means to open and close thetoggle mechanism in desired sequence, an eccentric fixedly secured onthe rotatable member for rotation therewith and forming the upper pivotfor the toggle mechanism with rotation of the eccentric raising andlowering the toggle mechanism to vary the distance between the pressuremembers, a gear secured to the rotatable member, a rack engaging saidgear with movement of said rack adapted to rotate the rotatable memberand the eccentric, adjustable stop means associated with the rack topredeterminately limit the movement of said rack and thereby controlrotation of the eccentric, and pressure means for imparting movement tothe rack, with the rack moving a predetermined amount as established bythe stop means adjustment and thereby setting the height of the movablepressure member with respect to the other pressure member.

2. In a metal forming apparatus wherein a blank is formed by successivepasses between a pair of pressure members with one of the members beingdisposed for vertical movement relative to the other of the members,aframe, a horizontal shaft rotatably disposed on said frame, a togglemechanism interconnecting the shaft and a movable pressure member toeffect vertical movement of the movable member in accordance withopening and closing of the toggle mechanism, means to automatically openand close the toggle mechanism in accordance with the-number of passesto be made on the blank, an eccentricfixedly mounted on said shaft forrotation therewith and providing a pivot for the toggle mechanism withrotation of the eccentric raising and lowering the toggle mechanism tovary the distance between the pressure members, gear means disposed torotate said shaft, a pair of movable racks disposed to successivelyactuate the gear means and thereby progressively rotate the eccentric, aprojection disposed on each of said racks, adjustable stop meansassociated with said racks and adapted to be engaged by saidprojections, said stop means being disposed to be predeterminately setwith respect to said projections to control the amount of rotationdesired of the eccentric for each successive pass, said gear means beingprogressively actuated as the racks move from their initial positionsuntil the stop projections engage the adjustable stop means, fluidpressure actuated pistons convate the racks and thereby set the movablepressure member progressively downward relative to the other pressuremember for each subsequent pass at the blank.

3. A draw rolling mill, comprising a frame, a platen slidablydisposedfor reciprocation on the frame, a die member secured on the platen formovement therewith, means to reciprocate the platen for a predeterminednumber of successive automatic cycles, a pressure roll disposed forvertical movement relative to the die member to form a blank betweensaid roll and said die member, a shaft rotatably disposed on said frame,:a toggle mechanism interconnecting the shaft and the movable pressureroll to effect vertical movement of said roll in accordance with openingand closing of the toggle mechanism, means to open and close the togglemechanism in accordance with the platen reciprocation cycles, aneccentric fixedly mounted on the shaft for rotation therewith andproviding a pivot for the toggle mechanism with rotation of theeccentric raising and lowering the toggle mechanism to vary the distancebetween said roll and platen, a gear fixedly secured on said shaft, arack engaging said gear to actuate the gear and thereby rotate theeccentric and set the roll height, a floating gear connected to therack, a pair of racks to freely support the floating gear therebetween,said floating gear racks being successively actu ated to progressivelyadvance the floating gear and the rack connected thereto, projectionsdisposed on the floating gear racks, adjustable stop means associatedwith the floating gear racks and being adapted to be predeterminatelyset with respect to said projections to control the amount of rotationdesired of the eccentric for each successive pass, said racks and gearsbeing progressively actuated as the floating gear racks move from theirinitial position until the stop projections engage the adjustable stopmeans, and means to sequentially motivate the floating gear racks andthereby set the movable pressure member progressively downward relativeto the other pressure member for each subsequent pass on the blank. 4.In a metal forming apparatus wherein a blank is formed by successivepasses between a pair of pressure members with one of the members beingdisposed for vertical movement relative to the other of the members, aframe, a horizontal shaft rotatably disposed on said frame, a togglemechanism interconnecting the shaft and nected to the racks to motivatethe same, valve means to control thepressure fluid acting on saidpistons, and

a movable pressure member to efiect vertical movement of the movablemember in accordance with opening and closing of the toggle mechanism,means to automatically open and close the toggle mechanism in accordancewith the number of passes to be made onthe blank, an cecentric fixedlymounted on said shaft for rotation therewith and providing a pivot forthe toggle mechanism with rotation of the eccentric raising and loweringthe toggle mechanism to vary the distance between the pressure members,gear means disposed to rotate said shaft, a pair of movable racksdisposed to successively actuate the gear means and therebyprogressively rotate the eccentric, projections disposed on said racks,adjustable,

stop means associated with said racks and adapted to be predeterminatelyset with respect to said projections to control, the amount of rotationdesired of the eccentric for each successive pass, said gear means beingprogressively actuated as the racks move fromtheir initial positionsuntil the stop projections engage the adjustable stop means, fluidpressure actuated pistons connected to the racks to motivate the samethrough the predeterminately set distance, a solenoid valve operablyconnected to each fluid pressure actuated piston to control the fluidpressure acting on said pistons and thereby move the racks, switches,electrically connected with said solenoid valve to energize the same,and cam means operably connected to said switches to operate thesolenoid. valves and sequentially motivate the racks and thereby set thepressure roll progressively downward relative to the die member on eachsubsequent pass to impart the desired form to awar jbp r e s id e v t ma t e u ia y mgtih;

' l I 5. In a draw'rolling mill"wherein a blank is' formed by means of apredetermined number of successive automatic passes between a pressureroll and a die member with the roll being disposed for vertical movementrelative to the die member, a platen to support the die member and beingslidably disposed for reciprocation on the bed of the mill, drive meansto reciprocate the platen, fluid pressure clutch means operablyconnected to the drive means to effect reciprocation of the platen whenthe clutchmeans is engaged, fluid supply means for supplying fluidpressure to said clutch means, valve means operably connected to saidfluid s-upply'means for con trolling the flow of fluid from said supplymeans to said clutch means, means responsive to operation of said drivemeans for actuating said valve means and engaging said clutch means toreciprocate the platen, means responsive to a predetermined number ofpasses made on the blank for actuating said valve means and disengagingsaid clutch means to stop reciprocation oi the platen, and actuatingmeans interconnecting the pressure roll and the drive means to raiseandrlower the pressure 'rollfrelative to the die member in sequence withthe platen reciprocations to form the blank therebetween.

6. Ina draw rolling mill wherein a blank is formed by means of apredetermined number of successive automatic passes between a pressureroll and a die member with the roll being disposed'for vertical movementrelative to the die member, a platen to support the die member and beingslidably disposed for reciprocation on the bed of the mill, drive meansto reciprocate the platen, fluid pressure clutch means operablyconnectedto said drive means to effect reciprocation of the platen when theclutch means is engaged, fluid supply means for supplying fluid pressureto' said clutch means, valve means operably connected to said supplymeans for controlling the flow of fluid from said supply. means to saidclutch means, switch means operablyconnected to said valve means andactuated by operation of said-drive means for opening said valve meansand, supplying fluid pressure to said clutch means to eflect engagementof said clutch means and thereby reciprocate the platen, second switchmeans operably' connected to said valve means and actuated by said drivemeans for closing said valve means after a predetermined number ofpasses have beenmade on the blank to disengage said clutch means and.stop; reciprocation of the platen; and actuating meansinterconnectingthe pressure 'roll and the drive means to raise and lowerthe pressure rollrelative to the die member in sequence with the platenreciprocaa tions to form the blank therebetween. A e

7. In a draw rolling mill wherein'a blank-is formed by means of apredetermined number of successive automatic passes between a pressureroll and a die member with the roll being disposed for vertical movementrela: tive to the die member and being adapted for automatic adjustmentrelative to the die member totake a progressively larger bite at theblank on each. succeeding pass, a platen slidably disposed forhorizontal reciprocation on the 'frame ofthe mill with the die memberbeing rernovably secured to the platen for movement therewith,

drive means to reciprocatethe platen, fl uid pressure clutch meansoperably connected to the drive means to effect reciprocation of theplaten when the clutch means is engaged, fluid supply means forsupplying fluid pressure to said clutch means, a solenoid valveconnected'to the fluid supply means to control the flow of fluid to saidclutch means and effect engagement'of'the clutch means and reciprocationof the platen, a plurality of switches arranged in parallel circuit toeach other and in series circuit with the solenoid valve with one ofsaid switches being operative at a given time to energize the valve, aplurality of rotating cams operably connected to one each of saidswitches with each cam rotatingat a different cyclic rate whereby.onerevolution of each cam corresponds to a predetermined number ofplateni'ecipro cations, one of said cams acting to maintain-the operative switch closed for one cam revolution to thereby engage the clutchmeans for a predetermined period of time, actuating means connected tothe ,drive means to rotate the cams at their respective cyclic ratesafter the clutch is engaged, a separate selector switch arranged inseries circuit with each of the first named switches, means disposed toselectively engage one of the selector switches to close said selectorswitch and thereby place one of the first named switches in theoperative circuit, means to initially engage the clutch and start thedrive means for the platen and the actuating means for the rotatingcams,said drive means and said actuating means operating until the cam actingto'rnaintain the operative switch closed has. completed one revolution,said cam serving to open the operative switch after the same hascompleted one revolution and thereby stopping the drive means and saidactuating means, a toggle mechanism interconnecting the pressure rolland the frame of the mill to raise and lower the pressure roll relativeto the die member, and means interconnecting the toggle mechanism andthe drive means to operate the toggle'mecha'nism and thereby raise andlower the pressure roll in sequence with the platen reciprocationsto-form the blank between the pressure roll and the die member.

- 8. A draw rolling mill, comprising a frame, a platen slidably disposedfor reciprocation onthe frame, a die member removably secured to theplaten for movement therewith, a-pressure roll disposed for verticalmove ment relative to the die member, said pressure roll and said diemember cooperating to form a blank by means of a predetermined number ofsuccessive automatic passes therebetween, drive means to reciprocate theplaten, fluid pressure clutch means operably connected to said drivemeans to effect reciprocation of the platen when the clutch means isengaged, fluid supply means for supplying fluid pressure to said clutchmeans, a valve operably connected to the fluid supply means to controlthe flow of fluid and to effect engagement of the clutch means andreciprocation of the platen, meanstto actuate said valve andtherebyengage the clutch means and reciprocate the platen for apredetermined period of time corresponding to the predetermined numberof successive automatic passes to be made on the blank, actuating meansinterconnecting the pressureroll and th drive means to' raise and lowerthe pressure roll relative to the-die member in sequence with the platenreciprocations'to form the blank therebetween, and means toautomatically set the roll relative to the die member to take aprogressively larger bite at the blank on each succeeding pass.

9. A draw rolling mill for forming a blank by means of a predeterminednumber of successive automatic passes between a pressure roll and a diemember with said roll being disposed for vertical movement relative tovthe die member comprising, a platen slidably disposed tor reciprocationon the bed ofthe mill with the die memher being remova-bly secured"thereon, drive means to reciprocate the platen, fluid'pressure clutchmeans operably connected to said drive means toeflect reciprocationofthe' platen when the clutch means is engaged, fluid supply means forsupplying fluid pressure .to said clutch means, an electrically operatedvalve operably connected to the fluid supply means to control the flowof fluid and to effect engagement o f'the clutch means reciprocation ofthe platen, a plurality of switches arranged in parallel circuit toeachother and in series circuit with the valve with any one of saidswitches being selectively operative at a given time to energiie thevalve, a plurality of separate ineamfil y melet whichis adapted to beoperably connected-with a correspond ing switch .to maintain thecorresponding switch closed and therebyengage the clutch means andreciprocate the platenifor a predetermined period "of time correspondingto the predetermined number of successive auto matic passes to be madeon'the blank,'rneans toraise and lower the pressure roll relative to thedie member in sequence with the platen reciprocation to form the blanktherebetween, and means to automatically set the roll relative to thedie member to take a progressively larger bite at the blank on eachsucceeding pass.

10. A draw rolling mill for forming a blank by means of a predeterminednumber of successive automatic passes between a pressure roll and a diemember with said roll being disposed for vertical movement relative tothe die member comprising, a platen to support the die member andslidably disposed for reciprocation on the bed of the mill, drive meansto reciprocate the platen, fluid pressure clutch means operablyconnected to said drive means to eflect reciprocation of the platen whenthe clutch means is engaged, fluid supply means for supplying fluidunder pressure to said clutch means, a solenoid valve operably connectedto the fluid supply means to control the flow of fluid and to efiectengagement of the clutch means and reciprocation of the platen, aplurality of switches arranged in parallel circuit to each other and inseries circuit with the solenoid valve with only one of said switchesbeing in the operative circuit at a' given time to energize the valve, aplurality of cams any one of which is adapted to be operably connectedto a corresponding switch with one of said cams acting to maintain acorresponding switch closed and thereby engage the clutch means andreciprocate the platen for a predetermined period of time correspondingto the predetermined number of successive automatic passes to be made onthe blank, means to raise and lower the pressure roll relative to thedie member in sequence with the platen reciprocations to form the blanktherebetween, and means to automatically set the roll relative to thedie member to take a progressively larger bite at the blank on eachsucceeding pass.

11. A draw rolling mill for forming a blank by means of a predeterminednumber of successive automatic passes between a pressure roll and a diemember with the roll being disposed for vertical movement relative tothe die member, comprising a platen slidably disposed for horizontalreciprocation on the frame of the mill with the die member beingremovably secured on the platen for movement therewith, drive means toreciprocate the platen, fluid pressure clutch means operably connectedto the drive means to eflect reciprocation of the platen when the clutchmeans is engaged, fluid supply means for supplying fluid under pressureto said clutch means, a solenoid valve connected to the fluid supplymeans to control the flow of fluid and to effect engagement of theclutch means and reciprocation of the platen, a plurality of switchesarranged in parallel circuit to each other and in series circuit withthe solenoid valve with one of said switches being operative at a giventime to energize the valve, a plurality of rotating cams one of which isoperably connected to a corresponding switch with each cam rotating at adifierent cyclic rate and with one revolution of each cam correspondingto a predetermined number of platen reciprocations, any one of said camsbeing adapted to maintain the operative switch closed for acorresponding cam revolution to thereby engage the clutch means for apredetermined period of time, actuating means connected to the drivemeans to rotate the cams at their respective cyclic rates after theclutch is engaged, a plurality of selector switches one of each beingadapted to be arranged in series circuit with a corresponding firstnamed switch, a manually operated selector cam disposed to selectivelyengage one of the selector switches to close said selector switch andplace one of the first named switches in the operative circuit, means toinitially engage the clutch and start the drive means for the platen andthe actuating means for rotating the cams, said drive means and saidactuating means operating until the cam acting to maintain the operativeswitch closed has completed one revolution, said cam serving to open theoperative switch after the same has completed one revolution and therebystopping the drive means and said actuating means, means interconnectingthe pressure roll and the drive means to raise and lower the pressureroll relative to the die member in sequence with the platenreciprocations to form the blank therebetween, and means toautomatically set the roll relative to the die member to take aprogressively larger bite at the blank on each succeeding pass.

12. In a metal forming apparatus wherein a blank is formed between apair of pressure members with one of the members being disposed formovement relative to the other of the members, a frame, a rotatablemember disposed on said frame, a toggle mechanism interconnecting therotatable member and a movable pressure member to eifect movement ofsaid movable member in accordance with opening and closing of the togglemechanism, drive means connected to the toggle mechanism for opening andclosing said toggle mechanism in desired sequence, eccentric meansconnected to the toggle mechanism for successively changing the positionof closing of said toggle mechanism to correspondingly vary the distancebetween the pressure members, actuating means operably connected to saideccentric means and responsive to a predetermined amount of movement ofsaid drive means for automatically actuating said eccentric means tosuccessively decrease the distance between the pressure members for eachsuccessive working stroke of the movable pressure member, and adjustablemeans connected to said actuating means to selectively limit theoperation of said actuating means and thereby control the rotation ofthe eccentric means.

13. In a metal forming apparatus wherein a blank is formed between apair of pressure members being disposed for movement relative to theother of the members, a frame, a rotatable member disposed on saidframe, a toggle mechanism interconnecting the rotatable member and amovable pressure member to efli'ect movement of said movable member inaccordance with openingand closing of the toggle mechanism, eccentricmeans connected to the toggle mechanism for changing the position ofclosing of said toggle mechanism to correspondingly vary the distancebetween the pressure members, said eccentric means having at least threeseparate positions of operation corresponding to three separatedistances between said pressure members, and means operably connected tothe eccentric means and actuated by rotation of the drive mechanism forautomatically moving the eccentric means to each of said positions tosuccessively decrease the distance between the pressure members for eachsuccessive working stroke of the movable pressure member.

References Cited in the file of this patent UNITED STATES PATENTS498,839 Billings June 6, 1893 514,820 Fletcher Feb. 13, 1894 627,936Kuhlewind June 27, 1899 662,445 Kuhlewind Nov. 27, 1900 1,056,203 NeaveMar. 18, 1913 1,840,059 Smith Jan. 5, 1932 2,006,765 Hudson July 2, 19352,014,475 Hughes Sept. 17, 1935 2,057,924 Smith Oct. 20, 1936 2,200,837Fass May 14, 1940 2,237,040 Peterson Apr. 1, 1941 2,613,560 RozieresOct. 14, 1952 2,745,530 Foster May 15, 1956

